Need help, Arrange Marriage M33?

I got a proposal, the girl is 27. All my family member liked her and they know the family well. They say the girl is well behaved and family is very good. But to me she looks average, when I talked to her I am not getting much attraction. My family says I am making wrong decision as this is a very good match and I wont find any other match like this as they know the girl and family well. But I am not getting much attaction physically and mentally. Our aspirations dont match much. Family says that you will gain attraction after marriage as we too have got that. Girl is thin and they are saying that after marriage the girl looks more beautiful and becomes healthy. Guys pls give your suggestions.